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•
C to D:
Once modulation is established, the sensed loop temperature can fluctuate
between
155°F and
145°F
(between St4 and SR).
The firing rate increases or decreases proportionately between 100% and low
fire, depending upon the temperature sensed in the return loop. Temperature rise in the heat exchanger
varies accordingly, 45° to 15° depending upon the firing rate.
•
D:
The unit will remain in modulation until the sensed temperature rises above
155°F (St4).
The firing rate
returns to low fire. Modulation will only reactivate when return loop temperature drops to 155°F.
•
E to F:
Low fire is maintained if the return loop temperature ranges between
155° and 165°F
.
•
F:
This firing pattern will continue until the temperature reaches the “Burner OFF” threshold of
165°F
(St1)
and shuts off
.
9.6 To View The Setpoint
•
Push and release the
SET
key to see the set point value.
•
To return to normal display, press
SET + UP
or wait 15 seconds without pressing any key.
9.7 To Change The Setpoint
•
Push
the
SET
key. The upper display will show the “St1” parameter name, while the lower display will show
its value.
•
Use
the
UP
or
DOWN
key to cycle through the parameter names.
•
Push
the
SET
key to modify a parameter value. The value starts flashing in the lower display.
•
To change it push the
UP
or
DOWN
keys. Push the
SET
key again to confirm the value and pass to the
setting of next set point.
•
Repeat the operations described at points 3, 4, 5.
•
To Exit:
press
SET + UP
or wait 15 seconds without pressing any key.
NOTE:
Each point has a time out of 15 seconds. If any key is pushed within 15 seconds the controller exits the
set points programming procedure.
NOTE
: The set value is stored even when the procedure is exited by waiting the time-out to expire.
9.8 To Change Other Parameters
•
Push
the
SET
and
DOWN
arrow simultaneously for 3 seconds.
•
Select the required parameter. The name of the parameter is on the upper display; its value is on the lower
display.
•
Press
the
SET
key: the value of the parameter will start blinking.
•
Use
UP
or
DOWN
to change the value.
•
Press
SET
to store the new value and move to the following parameter.
•
To Exit
: Press
SET + UP
or wait 15s without pressing a key.